As of Feb 2020, Gacha crystals can only be of rarity Apprentice or lower. Still gives some decent loot, but nothing like the Ascendant farm it used to be.

Feed Owl pellets and stone for Asc and other rarity crystals!

When raising a baby gacha, fill their inventory with stacks rare mushrooms. They don't prefer them over other foods, but they will eat them if they have to and each mushroom regains alot of food. This will keep them from starving. This is really easy on aberration. They will still drain your berry troughs, but this will give you peace of mind when you've got other things to do. "UP" if this helps at all.

Gachas are essentially living lootboxes and resource farms. They will eat anything (including stone, wood, or fiber) and turb it into crystals which can drop a variety of resources including black Pearl's, organic polymer, or obsidian, among other things. They also have a rare chance to drop higher-tier crystals which turn into upgraded armor and tools